Pulse Skipping Modulated DC to DC Step Down Converter Under Discontinuous Conduction Mode

Reduced switching loss favours Pulse Skipping Modulation mode of switching dc-to-dc converters at light loads. Under certain conditions the converter operates in discontinuous conduction mode (DCM). Inductor current starts from zero in each switching cycle as the switching frequency is constant and not adequately high. A DC-to-DC buck converter is modelled and simulated in this paper under DCM. Effect of ESR of the filter capacitor in input current frequency components is studied. The converter is studied for its operation under input voltage and load variation. The operating frequency is selected to be close to and above audio range.

Authors:

• Ramamurthy S
• Ranjan P V
• Raghavendiran T A

Keywords:

• Buck converter
• Discontinuous conduction mode
• Electromagnetic Interference
• Pulse Skipping Modulation.

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